This invention relates to an improved process for extracting phenol from a phenol-water mixture. More particularly, it relates to carrying out the aforementioned extracting using an extracting medium comprising an aromatic hydrocarbon component and a ketone component.
The recovery of phenol from aqueous phenolic mixtures using benzene as the extracting solvent, for example from (1) tar water, (2) aqueous phenolic wastes, and (3) aqueous coke-oven wastes, is described in articles by (i) B. I. Ivanov et al., (ii) L. I. Zlatin et al. and (iii) Zd Aunicky. These articles are cited in the Chemical Abstracts of the American Chemical Society at Vol. 54:15905i, Vol. 59:13683e and Vol. 63:393e, respectively. However, the phenol extraction coefficient for the benzene-water system is small, for example it is less than 5. The lower the coefficient, of course, the larger is the number of extraction stages which must be used for an effective recovery of phenol in an extracting process and the larger is the amount of solvent which must be processed. Accordingly, there is a need for a phenol extracting medium having an improved extraction coefficient.
It is an object of this invention to provide an extracting medium having an improved extraction coefficient. A further object is to provide an improved process for recovering phenol from water-phenol mixtures using such a medium.